Yamaha YPAO R.S.C – Take Two

Introduction

In a previous blog post, I introduced YPAO R.S.C. (Reflection Sound Control), which is Yamaha’s room equalisation system. If you’re new to room equalisation, please read this post first. I will present some measurements below to show what R.S.C. is doing exactly.

Function of R.S.C.

According to Yamaha, the pure function of R.S.C. is to remove unwanted first order reflections from the sound. This should improve stereo imaging and intelligibility. As we will see there are other added benefits.

R.S.C. filters are applied before any Parametric Equalisation. In fact, all further measurements were taken using the following method on an RX-V3073 (the equivalent of the RX-A3020.

  1. Running a multi-position YPAO with all 8 speaker positions.
  2. Copying the flat curve over to the manual curve. This also copies the R.S.C filters as we will later see.
  3. Zeroing out the PEQ filters manually (to 0dB on all) as this will keep the R.S.C. filters but remove any parametric equalisation. This has also been confirmed by Yamaha Japan – and the measurements that follow.

Measurements

YPAO succeeds in its goals – with some speakers and seating positions better than with others. I will show an example below with a centre speaker measurement. The centre speaker is located underneath a tensioned screen. The speaker is tilted upwards towards the listening positions. However, because of the room dimensions and multiple hard surfaces between the speaker and the listening positions on the sofa, the 70Hz to 250Hz region is a real issue with room modes – peaks and dips galore – that reduce intelligibility and are hard to deal with using PEQ alone.

Frequency Sweep

The below frequency sweep has 1/6 octave smoothing so all that is visible that R.S.C. cut some reflections in the 60Hz to 200Hz region. The green line was measured in the “through” position, while the pink line in the manual setting with no PEQs applied. Please note that R.S.C. is applying some attenuation to the signal output. The attenuation is dependent on the filters applied by the system, so it varies from channel to channel. The graph below has been adjusted to take this into consideration.

It is interesting to note that there is some activity going on above the modal region (above 250Hz). This isn’t necessarily bad as long as the robustness of the correction is taken into consideration. For example, Dirac Live does this across the whole spectrum also, but the higher frequencies are corrected, the more correlation needs to be between samples.

center rsc v no

Now let’s have a look at the modal region with less smoothing to see what’s really going on there. Now this is more interesting. R.S.C. actually dealt with a dip in the 70Hz to 80Hz region, where the subwoofer crosses over to the centre speaker and removed some frequency build-up because of the back and side walls between the 80Hz to 200Hz.

center rsc v no v2

So what is actually going on in the 70Hz to 80Hz region? Obviously no PEQ filter would be able to fill that region in since waves are cancelling each other out – as that has been tried before on this set-up. Let’s have a look at what is going on in the phase of the signal to answer that question.

Phase Measurements

As can be seen in the below measurement without any R.S.C. filters applied, there is a phase shift in the crossover region. This is quite common.

center phase no eq

As can be seen in the below measurement with R.S.C. applied, the subwoofer and centre speaker phase are better aligned in the crossover region, therefore removing the dip in the frequency measurement. So far so good.

center phase rsc

Ringing

Finally, let’s look at the spectrogram to see whether ringing has been improved. To be honest, ringing wasn’t much of an issue for this speaker / seating position. But as we can see in the after diagram, the crossover region looks a lot smoother and overall sound pressure levels have been better equalised in the modal region.

center spect no eq

center spect rsc

Subjective Listening Tests

After the above measurements were made, the PEQ filters got re-applied that smoothed the frequency response out, now having a much easier job of doing so.

Having the same PEQ applied over R.S.C. and no R.S.C. filters, though not a perfect test, the sound with R.S.C. filters applied just seemed more 3 dimensional with a better stereo image from the front and surround channel pairs. The sound of the centre channel is also improved in terms of smoothness.

What’s also clear is that the bass region is improved in terms of tightness. Even though amplitude was corrected with PEQ filters, the bass still sounded boomy in some listening positions without R.S.C. applied.

Tips and Tricks

The above does pose a challenge for those that like to have the Yamaha presence channels going along with the base 5.1 or 7.1 set-up and want to do a “full manual” configuration with R.S.C. applied. How do you measure the frequency response of these speakers after R.S.C. has been applied? Here’s a neat trick:

The easiest is to feed the left, right or surround left and right speakers with the frequency sweep signal while having the receiver in 9 channel / 11 channel stereo mode.

To hear the signal only come through the corresponding presence speaker, configure the 9 channel stereo to maximum high balance, maximum strength and maximum front / rare – left / right balance as needed. This will channel around 80% of the energy through the measured speaker, which is good enough to get an accurate measurement.

Happy Listening!

Advertisements

The Home Cinema PC – Simply!

Introduction

I love packaged media such as DVD – in the old days – and now Blu Ray. Packaged media will always have the upper hand when it comes to quality of picture and sound so let’s hope it’s here to stay. Nevertheless, there are so many of us who download TV shows or even want to have easy access to a library of movies without having to lift our back sides off that comfortable couch.

Since this problem is not new, many options are now available to do just what we want from Microsoft Media Centre PCs and appliances to games consoles like the Xbox One. In the following pages, I will show you my favourite solution that delivers the best balance of usability, features and quality.

XBMC – now Kodi

The-new-home-screen-of-XBMC-OpenELEC

XBMC – or Kodi by its new name – is an open source, free application that anyone can download from the net. It has been around for years and it is my favourite choice for the following reasons:

  1. The audio and video quality when using an HDMI connection is excellent, regardless of the platform used: from Windows to Apple OS X to Linux.
  2. It is fully configurable to how you want it.
  3. It integrates with online movie and TV databases and downloads art, trailers and everything in between to store locally in your media library.
  4. It just works.

Choosing the hardware

having A dedicated PC

After much research, I chose to use an Intel NUC. Intel NUCs are small – actually tiny – form factor PCs that come with a processor, but not RAM. You will need to buy that separately. What is great about them is that they are cheap, don’t require a lot of effort to build, look great and have all the connections you need – including an infrared sensor for your remote.

If you’re only after 1080p (full HD) playback, any of the NUCs will do, even the celeron based ones. If you have a new 4K TV and want to future-proof your media playback device, you should buy one of the top performing NUCs as 4K is very CPU intensive: it uses a new codec (HEVC) that cannot be hardware decoded on current graphics processors.

414033-intel-nuc-kit-d54250wyk

Now you may find other off the shelf PCs for a similar price, so do have a look around.

The other option – if you’re adventurous, don’t have a lot of money and want to build your own PC – is to use a Raspberry Pi. There are many guides on how to build one on the Internet. Google is your friend!

openelec – turn your pc into an appliance

If you’re using a dedicated PC for your home cinema and you want to use XBMC, there is no better option than Openelec. Openelec is a stripped down Linux distribution that boots straight into XBMC without any other hassles. While you could make Windows or Linux boot straight into the desktop and then open XBMC, Openelec starts up faster, is more stable and can be upgraded with a remote control. The same cannot be said for Windows, but especially Linux. Plus with Openelec you remove all the added distraction that Windows brings with itself.

There are also many guides on the net on how to install Openelec so we won’t go into that here. Again, Google is your friend!

Installing xbmc / kodi on your current computer or other device

It is also possible to install XBMC on your current Windows, Apple or Linux computer and even on the Apple TV and android device. It is great to do this to try our XBMC and see if you like it first. You simply download the relevant installed from the Internet and off you go.

Choosing a remote control

Pretty much any remote control that’s been built for Microsoft Media Centre will work. The one pictured below can be had for as little as AU$15 on Ebay and has been tested to work. In fact I use one of these in my Home Cinema.

170156-hp-pavilion-media-center-tv-m8100y-pc-remote

Configuring XBMC / Kodi

audio / video configuration

To get the most out of XBMC, pay extra attention to the following configuration aspects under settings. You may need to switch the settings pane to “Expert” to get access to some of the settings.

  1. For maximum picture quality, XBMC allows you to match the refresh rate of your display to your video OR match the refresh rate of your video to your display by speeding it up or down as necessary. These settings are under System –> Video and should be enabled. One or the other should work on all systems.
  2. For maximum sound quality, especially if you’re using an external receiver or amp that has Dolby D and DTS decoding, set the audio to bitstream in settings and tick which formats your receiver supports. These settings are under System –> audio.

VideoPlaybacksettings_1

LIBRARY CONFIGURATION

It is best to store files on a NAS – such as a QNAP – or alternatively using external HDDs. Whatever the case, XBMC allows you to add new folders to your library under the file menu for movies and TV shows.

Once you have added the folders, XBMC will ask you what the folder contains and what (online or local) service to use to download movie / TV show information and art.

SPICE IT UP – SKINS

XBMC comes with a default skin called Confluence. It is functional. But XBMC can do a whole lot more. You can download and install new skins within XBMC or by downloading them from the Internet. One of my favourite is Aeon MQ (3/4/5 or 6). The skin is highly configurable and very functional and pretty.

44031246

I hope that wetted your appetite for building an easy to use media playback device easily and cheaply. Enjoy!

Uncompressed Sound and Video are NOT Better than Compressed

The Marketing Machine

Everyone was rejoicing when Blu Ray’s standard allowed manufacturers to include uncompressed sound on disks. Most certainly Blu Ray’s provide much improved sound but did you know that even DVDs allowed sound with more precision than some of today’s Blu Ray’s have? Let me explain…

Perceptual Coding

Perceptual coding in terms of audio and video means removal of information that cannot be perceived or distinguished by the human visual or auditory systems (your eyes and your ears). In even simpler terms, it is removal of stuff that you would not actually notice if it was removed. Why is this important? Well, it allows us to cram a 3 hour movie on a disk at a quality that would normally take about 25 Blu Ray disks.

If you have limited space or bandwidth, perceptual coding is ALWAYS going to give you better quality than lossless / uncompressed data. This is true for both video and audio. For example, if we were to take the data rate of uncompressed audio on Blu Ray today and we were to use perceptual coding using the same bitrate, we would be able to allocate more bits and more precision to data that we can actually perceive which would give higher perceived quality. In the same space, we could have movie soundtracks running at 96Khz sampling rate (96 samples a second) and 32bit precision of the individual samples, which would give audio a completely lifelike sound.

The Reality of Movie Soundtracks

Unfortunately, when it comes to movie soundtracks – unlike music – very few have been recorded and mixed at the higher sampling rate. This means that uncompressed sound at the current sampling rate (48Khz) and bit precision (16 to 24bits) is as good as it gets until studios decide otherwise. But it is good to know nevertheless that you don’t necessarily want lossless coding, especially when you have limited bandwidth. Lossy coding – if done correctly – will give better sound and picture at the same bandwidth.

While We Wait

While we wait, there are ways that sound can be much improved in a Home Cinema. I will be talking about these in the coming weeks.

What is Room Equalisation (EQ) and why should you care?

The Perfect Loudspeaker

Loudspeaker design nowadays is advanced to a point where loudspeakers have a pretty much flat frequency response between 20Hz to 20Khz, which are the lower and upper boundary of human hearing. In an ideal home cinema, the main speakers reproduce frequencies from 80Hz up while the subwoofer is reproducing frequencies from 80Hz down (in simplified terms). Sounds below 80Hz cannot be localised by human hearing (that is you cannot tell where the sound originated from) and because of the complexities of sound waves interacting below 80Hz in small rooms, it is best to have only one (or more) carefully placed subwoofers reproducing these lower frequencies.

Here Comes the Room

It’s great we have such advanced loudspeaker design, but once you put the speakers into a room, things get messy. The sound waves will reflect off the surfaces of the walls and furnishings and interact to create drips and peaks in the frequency response, making some frequencies louder, others quieter and yet others to echo and ring as they decay.

vergleich-absorberExample of frequency response of a loudspeaker in a room

What is even more upsetting is that this is not uniform in the room. As you move your head, sit somewhere else or walk around, the dips and peaks change. If you have just spent 100’s or 1000’s on speakers, the situation is rather unacceptable. You obviously want to get the most out of your equipment.

EQ to the Rescue

There are two main ways to combat the above: digitally using equalisation and with acoustic treatments. The former is somewhat easier to implement and a lot more wife (or for our lady enthusiasts, husband) friendly.

Digital Room Equalisation is built into most receivers nowadays. Some are more effective than others. Let’s have a look at some of what is currently on the market:

Audyssey MultiEQ XT and MultiEQ XT32: Audyssey’s technology deals with the most problematic frequencies below 200Hz very well, especially when it comes to MultiEQ XT32. At the same time, higher frequencies may not sound natural to some listeners. Some manufacturers (such as Denon) allow you to apply it to only the bass frequencies for this reason. MultiEQ XT32 was also available in standalone products as SVS AS-EQ1 and Audyssey’s own branded subwoofer equalisers. They have been discontinued, however. It’s worth picking up a used one if you have a receiver that lacks a good subwoofer equaliser.

Yamaha YPAO and YPAO R.S.C: Yamaha YPAO and YPAO R.S.C are discussed in detail here. They both do a great job with frequencies above 80Hz. Fortunately, the implementation in most recent Yamaha receivers is fully editable using Parametric EQ, which gives you enough resolution to tackle most issues. The only exception to this is ringing of the modal frequencies (see below), which is important for subjective sound quality.

Parametric EQ solutions: a fully parametric EQ solution, such as the ones from MiniDSP, allow you to target the modal frequencies in the room precisely, therefore allowing the reduction of ringing / echoing of sound in the lower frequencies. A good parametric EQ is therefore essential for frequencies below 80Hz and good to have below 200Hz.  Neither Audyssey or YPAO tackle ringing at these problematic frequencies.

Dirac Live: Dirac is at the forefront of audio equalisation research and seem to be overtaking even Audyssey. Their impulse response correction algorithms seem to be gathering great reviews. More recently, they are also available in MiniDSP NanoAVR DL product, which makes it affordable. It is also very easy to use for those with not a lot of experience in equalisation, but who want to get the most out of their equipment. The highest end home cinema kits feature Dirac Live.

How to EQ?

If you’re new to home cinema, at the very least read your receiver’s manual and run the automatic calibration routine with all its feature set. If you’re more adventurous, you can supplement your system with a fully configurable parametric EQ for your subwoofer to tackle the modal frequencies in your room. For this, you will need:

  1. A parametric EQ connected between your receiver and your subwoofer
  2. The free Room EQ Wizard (REW) software from HomeTheatreShack.com.
  3. A compatible USB microphone.

To know more about how to measure your room and configure a Parametric EQ, the MiniDSP or HomeTheatreShack websites offers some good guides, but in essence you will have to:

  1. Install all the software
  2. Measure the room response (in this case for the subwoofer)
  3. Calculate the EQ filters automatically or manually in REW
  4. Input the filters into your choice of EQ
  5. Re-measure the altered frequency response
  6. Repeat until you get satisfactory results

Modal Frequencies and What to Do with Them

Modal frequencies in effect are frequencies excited or affected by the size of a room. The modal region is the region below which modal excitation happens. This is normally somewhere below 250Hz for medium to large home cinema rooms. What happens in the modal region is that certain frequencies – very accurately predicted by room dimensions – will combine and re-enforce each other or cancel each other out in a way that creates big differences in loudness and decay time of the frequency. This will make the rest of the frequency spectrum – especially frequencies close to the mode – smeared, masking detail and transparency of the sound reproduction. To resolve this, the modes need to be calculated and measured using REW using the Room Simulation module, then checked using a frequency sweep and waterfall diagram. Once the offending frequencies are found, Parametric EQ filters need to be designed to EXACTLY match the mode’s frequency and Q to rob the mode of its energy. This will help reduce decay time also and make the waterfall diagram more even.

waterfall - beforeWaterfall plot showing increased decay time in the modal region. The most offending modal frequencies are clearly visible at 29.6Hz and 71Hz. Interestingly, speech intelligibility is affected by a modal at 83Hz, even though it is not as visible on the diagram.

We have really only touched on some basic concepts when it comes to equalisation. Nevertheless, the topic deserves the attention of anyone serious about home cinema. Learn it or get a friend or consultant who has the knowledge. It makes more of a difference to the perceived sound quality than your choice of speakers or amplifier. This is because the tonal quality that you like in your speakers is a lot to do with the above graphs. Even cheaper speakers can sound fantastic with the right equalisation and a good quality subwoofer.

How to build a $300 screen that performs like a $2000 one

Now you can order pre-mixed paint from us. Please contact us for more.

The difference a screen makes

You can project onto a white wall and get a really great picture, but if you’ve spent more than $500 on a projector, you will notice a marked difference with a purpose built screen. The benefits of projecting onto a great screen include the following:

  1. Increased sharpness / perceived resolution of the image
  2. Increased contrast
  3. Better ambient light rejection (when using a grey or silver screen as below) which means you can watch TV, movies or Sports with some ambient light on without completely distorting contrast

Enter Projection Paint

There are some – may I say – rather expensive paints on the market that you can use to build a DIY screen. In this article, I will show you how to get the materials yourself, mix the paint, paint the screen and hang it.

Please note that this is a fixed frame projection screen, which means it is not really possible to paint a roll-up screen with the below method.

Getting the screen

There are a few options on where to paint the screen.

  1. If you have the wall-space you can paint the screen on the wall with a black frame or even paint the whole wall with the paint mix below to create an invisible screen… until the projector is turned on that is.
  2. If you cannot paint the wall, you have the option of getting an MDF sheet to paint or even better…
  3. Paint on 3-5mm foamex / forex PVC sheets. These sheets are really light and easy to work with. You can nail them to a wooden frame for hanging or even nail them to the back of some bookshelves.
  4. Any other rigid material that is paintable.

imagesForex Sheet

You can calculate the screen size you need at http://www.projectorcentral.com/projection-calculator-pro.cfm and get the materials cut to size, leaving enough outer rims for nailing and hanging.

Getting the paint

The paint mix is called Black Widow. I will show you how to mix and variate the colour shade of this paint mix to get the desired results. For now, let’s look at the base, no frills mix, for which you will need the following:

  1. A matt white water based paint. Any will do such as the Dulux Wash and Wear Matt white. The most important thing is that it is water based and matt. 2L is plenty for upto 140″ screen.
  2. You will need to ask the paint to be tinted using black paint to a grey to a shade of N7.8. If this is not possible an N8 will provide the right shade of grey also. If your trade centre doesn’t know how to tint paint using the N tint codes, ask them to call Dulux or a Dulux Trade Centre.
  3. You will need Auto-Air Colors 4101-16 Aluminum Base Fine paint, which is a water-based silver paint formula. You will need 4 parts white paint to 1 part Auto Air Colors. If you’re using 2L of white paint, this will mean 480ML of Auto Air Colors. Be sure to buy the “fine” coarseness.
  4. A short nap roller
  5. Fine sandpaper

313p5W+ljML._SY300_
Auto Air Colors

You will mix the above together using a drill and paint mixer head for 2-4 minutes

Painting the screen

  1. Using the paint mix, you will paint the surface with the roller in one direction only (vertical or horizontal) using quick movements. Go over it once quickly.
  2. Do NOT go over the surface again until it has dried.
  3. Once the first layer has dried, use the fine sandpaper to remove any imperfections from the surface.
  4. Remove any dust created by the sanding using a duster or a dry cloth.
  5. Repeat until you have at least 4-6 coats and a smooth even surface.
  6. Let the screen dry out completely before using it.
  7. Enjoy!

Variations on the above mix

The mix above comes out to a light to medium grey that is perfect for rooms with light coloured walls and bright projectors. It rejects ambient light well and has great contrast characteristics with the lights off as it rejects reflection from the light coloured walls.

If however, you are building a dedicated home cinema room with dark or black walls and you don’t intend on using the projector in ambient light, and you have a projector with great contrast (such as a JVC), you will want to mix a slightly lighter mix.

For a lighter mix, simply tint the white paint closer to N8.5, N9 or even N9.5. For 3D projection, which needs a lot of light, you could even try mixing with only a white base, as opposed to grey.

How to choose the right display?

There are so many brands, makes and types of displays on the market today that it is rather difficult to choose one for your living or home cinema room. In effect, there are 3 major things you need to look for when evaluating the quality of a display:

Black Level & Shadow Detail Performance

One of the most important aspect of perceived image quality is not resolution, as display manufacturers would like you to believe, but black level performance. A great proof of this is the switch from old CRT TVs with great black level to the then top of the range flat panel displays, which had rather poor black levels in comparison. Normal low-resolution TV broadcast looked better on the CRTs, while the new higher resolution flat panels needed specialised DVD players and trickery in signal processing to make images watchable.

sharp-mega-head
The difference between poor and great black level performance.

Black Level: how dark or deep the blacks look on the screen.

Because of how displays work, black level needs to be evaluated on dark as well as bright images and in moving from dark to bright images. The better the black level performance of the display, the more three-dimensional the images will look on the screen.

Shadow detail: how good a display is at resolving detail in darker areas (shadow) of the image.

If a display has dark inky blacks but it fails to resolve the subtle details in the darker areas of the image, the image will look flat especially on dark images or movie scenes. It is important that great black levels are married with great shadow detail performance to give a three-dimensional image regardless of the material.

Did you know that the brightness setting on your TV affects the black levels while the contrast setting affects the bright areas of the image? Just test the controls and notice what areas of the image change.

Brightness Performance

Even before resolution, how bright a display can go while maintaining its black levels contributes greatly to perceived image quality. The brighter the image can go, the more contrast your eyes will perceive – the contrast between the black and light areas of the image. The human eye will even perceive an image as higher-resolution simply because of the brightness of the image.

bright

In flat panel televisions, brightness is usually pretty average from display to display, but in projectors brightness plays an important part dependent on what kind of light control you have in a room.

In a normal living room with imperfect light control and light walls, projector brightness is more important than black level performance. While in a completely light-controlled room with black walls, black level performance becomes more important than brightness. Ideally you want a display that can do both.

For 3D performance, you will want high brightness again.

In flat panel displays, black level performance is more variable than brightness performance, therefore you should be paying more attention to that.

Resolution

There are three things under resolution you need to look our for.

Native Resolution

Native Resolution: the actual number of pixels available on the display.

Please refer to the diagram below regarding the type of resolutions currently available on displays.

resolutions-ultra-hd-4k-1080p-720p-dvdResolutions of modern displays

The amount of pixels you need to keep the image looking great depends on your viewing distance from the screen. As a guide, at the average viewing distance of 3 meters, you will notice the benefit of:

1080p / Full HD panel for any display above 30″ (display size is measured in inches diagonally).
4K for anything larger than 70″.

This means there is no actual benefit of buying a display with a resolution below those sizes at the distance of 3 meters for the average person.

Scaling Performance

Another area you need to look out for is how the display handles scaling.

Scaling: the transformation of an image from one resolution to another. For example, a DVD or TV image which has a maximum native resolution of 576p to 1080p.

Although most new material is now on Blu Ray and therefore 1080p natively, we still watch content on lower-resolution formats such as DVD and broadcast TV. The display needs to be tested regarding how well it handles this scaling. Some displays do this poorly but otherwise they perform well. In that case, you can still buy playback devices such as DVD players or set top boxes that do the scaling to the display’s native resolution to improve the image to bypass the internal scaling of the display.

Motion Handling / Motion Resolution

The last aspect of resolution is motion handling. It is also called “motion resolution”.

Motion Resolution: how well a display maintains image sharpness with moving images.

2707463101_cfb4a2ed34

Display manufacturers understand how important motion resolution is, so much so that they employ digital trickery  called frame interpolation – to reduce motion blur to keep image sharpness. You will want to turn any such trickery off and evaluate the display’s native ability to switch its pixels on and off using the same source device, such as Blu Ray player.

How to correctly evaluate a display?

This is the tricky part: as much as the above areas can highlight a display’s native performance, it is actually an interplay of the source device AND the display that will give you the end result. What does that mean? You need to evaluate the display’s ability using similar playback devices that you will be using at home, such as DVD players, Blu Ray players, TiVo, Gaming Consoles, etc.

Also, you need to set these devices up correctly to get the best performance out of the display: settings such as output resolution, output frame-rate, colour system, etc.

Which display technology?

So which display technology excels at all areas? It turns out some do better in some areas than others and it depends on your preference and situation as to what’s going to serve you best. The best thing to do is look out for the three areas above and trust your own eyes.

Flat panels:

Normal LCD Displays:

  1. Great native resolution, brightness and colour reproduction
  2. Below average black levels
  3. Below average motion resolution

LED and OLED Displays:

  1. Great black levels
  2. Great brightness
  3. Great all-around resolution
  4. Motion-resolution dependent on manufacturer and product

Plasma Displays:

Yes, they are still around, although in small numbers.

  1. Great black level performance
  2. Good brightness
  3. Below average motion resolution

Projectors

110679756_98fdd45346

DLP Projectors

  1. Class-leading brightness performance and motion resolution
  2. Great Colour reproduction – especially for 3-chip varieties
  3. Black level and shadow detail performance depends on manufacturer and product – goes from average to class-leading.

Recommended for brighter home cinema rooms as the high brightness will create a better perceived contrast. Also recommended for high-frame-rate material such as sports and 3D.

LCD Projectors

  1. Generally challenged black levels and shadow detail performance, although some manufacturers are better than others.
  2. Great brightness and colour reproduction
  3. Good but not great motion resolution.

Recommended when DLP projector is not suitable for viewers because of the DLP Rainbow effect.

XSDR – IDLA – LCOS

  1. Class-leading black level and shadow detail performance bettering even the best cinemas in the World.
  2. Historically low brightness over their lifetime more suited for dark home cinema rooms
  3. Motion-resolution has considerably improved but DLP still betters it.

Recommended for dedicated, light controlled home cinema rooms. The best cinemas use this technology for 2D viewing. DLP is still better for 3D.

How to wire up your speakers!

In my previous post, I explained how to position your speakers for surround sound. Next I would like to show you how to wire them up. This is something you do even before you plug your AV Receiver in.

It is really simple to do if you get the basic principles below.

Red and Black – Positive and Negative

All speakers will have two terminals: one for the positive and one for the negative side of the signal. They are usually coloured red for positive and black for negative.

  1. You will need to connect the red or positive terminal posts on your speakers to the red / positive terminal post on the AV receiver using your speaker cables.
  2. You will need to do the same with the black speaker terminals.

hSpeaker5-wayPost 11563
Speaker terminals on the back of two different speakers

To aid in the above, most speaker cables will have one side of the wire labelled with a + sign, while the other one with a – sign. Sometimes, only one or the other is labelled but in all instances it should make it easy to connect them up to the correct post.

Choosing the right speaker terminals

Your AV Receiver will have the red and black speaker terminal pairs labelled with the speaker positions: Front Left, Front Right, Centre, Surround Left, Surround Right, Surround Back Left and Surround Back Right. To understand what these positions mean, refer to my previous post.

You will simply need to connect the red and black terminals up to the matching speaker. What you absolutely need to ensure is that the wires don’t touch – at either your speakers or at the AV Receiver. Touching wires will cause a short circuit and could damage your AV Receiver and your speakers.

To attach the cables, unscrew the jumpers and insert the peeled wires from the side of the jumpers ensuring none of the unpeeled wire is hanging out on either side. Screw the jumper back on while holding the speaker cable in place. Ensure it is screwed back on tight so the cable cannot become loose.

images-1
Speaker terminal pairs on the back of an AV Receiver

Connecting your subwoofer

A subwoofer 99% of the time will have its own amplification, therefore it is not connected using a speaker cable and speaker terminals. It is connected to a pre-amplified signal output by your AV Receiver called a pre-out jack. You will find the subwoofer pre-out jack on the back of your amplifier under the area called Pre-Out.

HKH_AVR3700-Series-Full_PreAmp-Outputs_FBI_dv500x300
Pre-out jacks on the back of an AV Receiver

The cable you will need to connect your subwoofer with is called a single mono RCA to RCA cable or subwoofer cable. If your subwoofer has an LFE input, connect it to that input. If your subwoofer only has a line level input, connect it to that. These will usually be labelled accordingly on the back of your subwoofer. If there is only one RCA input, don’t try to figure out what it is, simply connect the cable.

To ensure the subwoofer is functioning correctly, set the crossover / high-pass filter to its maximum setting. This is usually a knob labelled ‘crossover frequency’ on the back of your subwoofer. This is needed because for home cinema, you need to let your AV Receiver handle bass management for this speaker. Lastly, don’t forget to plug the subwoofer in and power it on.

On higher-end AV Receivers, you may notice that all other speakers will have a corresponding pre-out jack. In an advanced post, I will show you how to use these for adding another amplifier as either an upgrade or for bi-wiring.

Bi-wiring

Some speakers have two sets of terminals connected by something called the jumper.

file_14_11
Double speaker terminals for bi-wiring

The double terminals can be used to bi-wire the speaker. Bi-wiring means connecting the same amplified signal to both the midrange and high-frequency drivers (or sets of drivers) to achieve double the power and get a cleaner sound.

Be-wiring requires an AV Receiver that has this feature or an additional external amplifier. Additionally, it requires advanced set-up of said equipment. I will show you in an advanced post how to do this. For now, just leave the jumpers on the speaker terminals and connect the speaker cable to the lower set of red and black terminals.